The substrate of the display panel in the conventional technology realizes angle-cutting by an angle-cutting means. The first lower limit value of the angle-cutting voltage is preset in the angle-cutting means.
The angle-cutting means currently used includes at least one comparator, since the comparator having a delay period, such as that the comparator having a delay period in the output flip. The angle-cutting voltage becomes the second lower limit value in the actual angle-cutting means, and the second lower limit value is less than the first lower limit value. Therefore the accuracy of angle-cutting voltage is deterioration, leading to the deterioration of product performance.